Holiday Entitlement for Irregular-Hours & Zero-Hours Workers (UK, 2024 Rules)

From April 2024, holiday for irregular-hours and part-year workers accrues at 12.07% of the hours they work. Here's what changed, who it applies to, and how to calculate it — with worked examples.

For leave years starting on or after 1 April 2024, holiday for irregular-hours and part-year workers accrues at 12.07% of the hours they actually work in each pay period. Someone who works 30 hours in a month earns 30 × 12.07% = 3.62 hours of paid holiday for that month. It builds up in hours, not days.

This replaced a confusing few years where the old 12.07% shortcut had been thrown into doubt by a Supreme Court ruling. If you employ casual, bank, zero-hours or term-time staff, here's what the current rules actually say — and how to work the numbers out.

Prefer to just get a number? Use the free irregular-hours holiday calculator.

Where does 12.07% come from?

Every worker is entitled to 5.6 weeks of paid holiday a year. In a 52-week year, that leaves 46.4 weeks actually worked. Holiday is earned across those worked weeks, so:

5.6 ÷ 46.4 = 12.07%

Each hour worked therefore earns 0.1207 hours of paid holiday. It's the same 5.6 weeks every other worker gets — just expressed as a running percentage instead of a fixed number of days, because the hours vary.

Who do these rules apply to?

The 12.07% accrual method applies to two specific groups, for leave years beginning on or after 1 April 2024:

  • Irregular-hours workers — those whose number of paid hours in each pay period is wholly or mostly variable under their contract (classic zero-hours and casual staff).
  • Part-year workers — those who, under their contract, work only part of the year and have periods of at least a week where they do no work and aren't paid (for example, some term-time-only staff).

Workers with fixed, regular hours — including most part-timers on set days — are not in scope. They keep the ordinary 5.6-weeks pro-rata calculation. See part-time holiday entitlement for that case.

Worked examples

Holiday accrued = hours worked × 12.07%:

Hours worked in the periodCalculationHoliday accrued
20 hours20 × 12.07%2.41 hours
40 hours40 × 12.07%4.83 hours
160 hours (a busy month)160 × 12.07%19.31 hours
1,000 hours (across a year)1,000 × 12.07%120.7 hours

Because it accrues in hours, it's taken in hours too. If you want a rough "days" figure, divide by the length of an average working day — but the legal unit is hours, and converting to days can mislead when shifts vary.

What about rolled-up holiday pay?

For these two groups only, the 2024 rules also re-permit rolled-up holiday pay: you can pay the holiday as a 12.07% uplift on every payslip instead of paying it when leave is taken. If you do this, it must be shown as a separate line on the payslip, and workers must still be able to take their leave — they just won't be paid again for it at the time.

Rolled-up pay is optional. The alternative is the accrual method above, where holiday builds up as a balance the worker draws down when they take time off.

Do they get bank holidays on top?

No. The 12.07% accrual already represents the worker's full statutory holiday, bank holidays included. There is no separate bank-holiday entitlement added on top for irregular-hours and part-year workers — unlike a salaried full-timer, whose contract may list bank holidays explicitly. (For how bank holidays work for everyone else, see UK bank holidays by region.)

Why did this change — what was Harpur Trust v Brazel?

The old 12.07% shortcut was widely used until Harpur Trust v Brazel (2022), where the Supreme Court ruled that a permanent, part-year worker (a term-time music teacher) couldn't have her holiday capped at 12.07% if that gave her less than the full 5.6 weeks. That left employers unsure whether 12.07% was safe to use at all.

The government's response was the 2024 reform: it restored the 12.07% method for leave years from 1 April 2024, but limited it to the two defined groups above — irregular-hours and part-year workers. For everyone else, the Brazel position and the ordinary pro-rata rules still apply. If a worker's arrangement is unusual, check current GOV.UK guidance, because this is an area that has moved.

Entitlement vs. pay — don't confuse them

Two separate calculations:

  • Entitlement — how much holiday they get (this guide): 12.07% of hours worked.
  • Pay — how much each hour of holiday is worth, based on a 52-week average of their earnings (zero-pay weeks excluded). See holiday pay including overtime.

Getting the entitlement right but the pay wrong (or vice versa) is one of the most common underpaid-holiday mistakes for variable-hours staff.

Doing it automatically

Tracking 12.07% of logged hours for every zero-hours and casual worker — every pay period, in hours, without quietly dropping below the statutory minimum — is fiddly to do by hand.

Coverboard accrues holiday for irregular-hours and zero-hours staff automatically from the hours you record, using exactly this 12.07% method, and keeps the running balance so nothing slips. You can sanity-check any single case first with the free irregular-hours holiday calculator.


This guide is general information, not legal advice. The rules for irregular-hours and part-year workers changed in 2024 and depend on the exact contract; for a specific worker, check current GOV.UK guidance or consult an employment law professional.